Hi,   We are using TPG as our NBN service provider; and we have our own domain and emails hosted by Netgistry.   We have been using MS Office 2013, along with Outlook 2013 as our mail client.  We configured to send/receive emails using <mail.ourdomain.com.au> for both incoming and outgoing mail server on port 110/587 without encryption.   I wanted to know if I can use TPG's outgoing mail server? I have tried to configure it following the suggested link (https://www.tpg.com.au/support/generalsetting.php) and have failed thus far using the settings belw:    incoming mail server: <mail.ourdomain.com.au> (port: 110) outgoing mail server: mail.tpg.com.au (port: 25) No SSL/TLS My outgoing server (smtp) requires authentication <ticked with username/password entered>   Can anyone shed some light please? As I was able to freely use ISP's outgoing mail server settings previously with other ISP (iiNet) in the past and I have yet to configure it right with TPG.  Am I missing something in the settings?   Outlook Error message: Send test e-mail message: Your outgoing (SMTP) e-mail server has reported an internal error. If you continue to receive this message, contact your server administrator or Internet service provider (ISP). The server responded: 554 5.7.1 [TPG-S02] [0AA5YESv003554] Message rejected    Thank you in adv, JF       ... View more